Tissue connector with tissue grasping protrusions equally spaced about the periphery of the connector at successive axial locations

ABSTRACT

A tissue connector has a first end, a second end, a body with a periphery and a plurality of tissue grasping protrusions extending from said periphery of said body. The plurality of protrusions are adapted to grasp tissue in one direction of movement of the connector through tissue and are not adapted to grasp tissue in an opposite direction of movement of the connector through tissue. At axial locations of said body, three of said protrusions are about equally located about the periphery of said body. At axial locations on a cylindrical periphery of the body, protrusions are located at about 120 degree spacings.

CLAIM TO PRIORITY

This application is a continuation of U.S. application Ser. No.11/968,494, filed Jan. 2, 2008, now allowed; which is a continuation ofU.S. application Ser. No. 11/747,085, filed May 10, 2007, now pending;which is a continuation of U.S. application Ser. No. 10/420,119, filedApr. 21, 2003, now U.S. Pat. No. 7,226,468, issued Jun. 5, 2007; whichis a continuation of U.S. application Ser. No. 09/629,428, filed Jul.31, 2000, now abandoned; which is a continuation of U.S. applicationSer. No. 08/324,529, filed Oct. 18, 1994, now U.S. Pat. No. 6,241,747,issued Jun. 5, 2001; which is a continuation-in-part of U.S. applicationSer. No. 08/055,989, filed May 3, 1993, now abandoned. All the aboveclaimed priority applications are incorporated herein by reference intheir entireties.

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates to a barbed tissue connector, and moreparticularly, to such a connector which can be used to quickly andeffectively close a body wound.

2. Description of the Prior Art

Human wounds are typically repaired with a filament introduced into thetissue by a needle attached to one end. After piercing the opposingfaces of the wound, the needle is removed, and the ends of the sutureare tied together with at least three overhand knots. Such a techniquerequires considerable time and expertise on the part of the surgeon.There are also a number of other drawbacks to repairing a wound in thismanner. For example, it is very difficult to use sutures to repairwounds where there is insufficient space to properly manipulate thesuture, especially those wounds repaired using fiber opticvisualization. The suture forms a loop as it is tied, and this loopconstricts blood flow to the tissue in its confines, promoting necrosisof the wound margins. Further, if the needle's passage was noncircular,the tissue will be distorted as it is secured by the suture.

Alternatives to conventional sutures are known in the prior art.Staples, as shown, for example, in U.S. Pat. No. 4,994,073, to Green,are often used for approximating the superficial layer of the wound.Staples, however, are generally unsuitable for deeper layers of tissue.

The patent to Alcamo, U.S. Pat. No. 3,123,077, discloses a roughenedsuture which can be passed through tissue in one direction, but resistsmovement in the opposite direction. The Alcamo suture, however, stillmust be sewn, as by a conventional technique, and the trailing end mustbe secured with knots. Thus, although there is less slippage of thesuture in the wound, most of the disadvantages of sutures noted aboveare also found in the Alcamo suture.

The patent to Tanner, U.S. Pat. No. 3,716,058, discloses a relativelyrigid suture with one or more barbs on opposite ends of an arcuate body.One disadvantage of the Tanner suture is that the rigid barbs, whichprotrude from the suture as it is inserted, will lacerate tissue andprevent retrograde repositioning. Further, since the barbs are onlyplaced at the ends of the suture, the forces applied to the tissue bythe barbs will be limited to a relatively small area; this substantiallyincreases the pressure on the blood vessels ensnared by a barb andseverely restricts blood flow to the area.

It will be seen from the foregoing that there is a need for a tissueconnector which can be placed more expeditiously than sutures, isself-retaining, obviates distortion of the tissue, can close tissueinaccessible to conventional procedures, and which preserves blood flowby broadly distributing the retention force.

SUMMARY OF THE INVENTION

It is an object of the present invention to overcome the aforementionedproblems in the prior art and to provide an improved tissue connector.

In accordance with the present invention there is provided a barbedtissue connector comprising: an elongated body having a point formed onone end, the body being formed of a material sufficiently hard for thepoint to pierce tissue and enable the connector to be inserted in tissuewhen a substantially axial force is applied to the body; and a pluralityof barbs projecting from the body, the barbs being disposed around theperiphery of the body along a length of the body which extends fromadjacent the one end to a predetermined location on the body, the barbsbeing configured such that they are yieldable in a direction toward thebody and are generally rigid in an opposite direction, and the barbsbeing sufficiently resilient to return to a predetermined position afterdeflection therefrom.

In one embodiment of the present invention, the barbed tissue connectorincludes an elongated body and a plurality of barbs which are disposedin a helical pattern on the body and extend from a pointed end of theconnector to a predetermined location on the body. Each barb includes afirst side, which forms an obtuse angle with the body, and a second sidewhich forms an acute angle with the body. The body is substantiallyrigid and sufficiently resilient to return to a predetermined positionafter deflection therefrom. When the connector is inserted in tissue torepair a wound, the pointed end pierces tissue and the barbs yieldtoward the body to facilitate entry of the connector.

When the connector has been placed in a desired position in tissue, thebarbs strongly resist movement away from this position. The connectorcan be inserted by gripping the connector in the hand and pushing theconnector into the tissue, or the connector can be inserted by means ofan inserting device which is withdrawn when the connector is in place.

A principal advantage of the barbed tissue connector of the presentinvention is that it permits a surgeon to rapidly and securely attachthe edges of a wound in human tissue without the necessity for threadingand tying numerous individual stitches or for the use of a complicatedor elaborate tool to insert the connector. The connector is configuredto minimize damage to tissue when inserted and to minimize scarring ortissue necrosis across the wound. The connector is capable of insertioninto the faces of a wound, can connect tissue at the bottom of a deepwound, and can connect tissue which is inaccessible to a staple.Finally, the connector of the present invention can be inserted quicklyand accurately by a surgeon who only has access to tissue from a smallopening or from only one direction, as, for example, during anendoscopic procedure.

Other features and advantages will become apparent upon reference to thefollowing description of the preferred embodiment when read in light ofthe attached drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a side view of the connector of the present invention, with asection broken away to more clearly show the arrangement of the barbs;

FIG. 2 is an end view of the connector shown in FIG. 1;

FIG. 3 is a side view of another embodiment of the present invention,with a section of a connector broken away;

FIG. 4 is a side view of another embodiment of the present invention;

FIG. 5 is a side view of another embodiment of the present invention;

FIG. 6 is a side view of another embodiment of the present invention;

FIG. 7 is a sectional view taken along the line 7-7 in FIG. 6;

FIG. 8 is a side view of another embodiment of the present invention;

FIG. 9 is a sectional view taken along the line 9-9 in FIG. 8;

FIG. 10 is a perspective view of an inserting device for use with abarbed tissue connector of the present invention; and

FIG. 11 is a view showing the inserting device and connector in a wound.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

The present invention allows a surgeon to rapidly and securely attachthe edges of a wound in human tissue without the necessity for threadingand tying numerous individual stitches or for using a complicated orelaborate tool. As used herein, the term “wound” means an incision,laceration, cut, or other condition where suturing, stapling, or the useof another tissue connecting device might be required.

With reference to FIGS. 1 and 2, there is shown a barbed tissueconnector 2 constructed in accordance with the present invention.Connector 2 includes a body 4 which is generally circular in crosssection and a plurality of closely-spaced barbs 6 which extend aroundthe periphery of the body 4. A pointed end 9 is formed on the body 4 tofacilitate penetration of the connector 2 into tissue. The body 4preferably has sufficient dimensional stability to assume asubstantially rigid configuration during use and is sufficientlyresilient to return to a predetermined shape after deflection therefrom.In some applications, it may be desirable for the body 4 to be flexibleand substantially nonresilient so that the shape of an insertedconnector will be determined by surrounding tissue.

Barbs 6 serve to hold the connector in tissue and resist retraction ofthe connector from the tissue. The barbs 6 can be arranged in anysuitable pattern, for example, in a helical pattern as shown in FIG. 1.In a helical pattern of barbs 6, it is preferable that the number ofbarbs occupying one revolution not be an integer, thereby avoidingparallel axial rows of barbs; such an arrangement provides a moreuniform distribution of forces on the tissue and lessens the tendency ofan inserted connector 2 to cut through tissue. If the number of barbs inone revolution is not an integer, the barbs in successive revolutionswill be offset, as shown in FIG. 2, and the amount of offset willdetermine which barbs are in axial alignment. For example, if the barbsin successive revolutions are offset by ½ barb, the barbs in everysecond revolution will be in axial alignment, and by extension, if thebarbs in each successive revolution are offset by 1/x barb, the barbs inevery x revolution will be in axial alignment.

As shown in FIG. 1, each barb 6 includes a first side 8 which forms anobtuse angle alpha with the body 4 and a second side 10 which forms anacute angle beta with the body 4. Each barb 6 tapers to a point 7, andthe amount of difference between the angle alpha of side 8 and anglebeta of side 10 will control the amount of taper in the barb 6. A barb 6which tapers from a broad base to a narrow tip can be effective inresisting retraction, yet will yield toward the body 4 during insertionto reduce the effort and tissue damage associated with insertion of theconnector 2. The barbs 6 can be generally conical, as shown in FIG. 1,or they can be any other shape which will function in substantially thesame manner as the conical barbs.

The configuration of barbs 6 and the surface area of the barbs can varydepending upon the tissue in which the connector 2 is used. Theproportions of the barbs 6 can remain relatively constant while theoverall length of the barbs and the spacing of the barbs are determinedby the tissue being connected. For example, if the connector 2 isintended to be used to connect the edges of a wound in skin or tendon,each barb 6 can be made relatively short to facilitate entry into thisrather firm tissue. If the connector 2 is intended for use in fattytissue, which is relatively soft, the barbs can be made longer andspaced farther apart to increase the holding ability in the soft tissue.As shown in FIG. 1, the barbs 6 on connector 2 have a uniformunidirectional configuration, that is, the barbs 6 are uniformly spacedon body 4 and all the sides 8 are oriented in the same direction, facingpointed end 9. Connector 2 can be inserted into tissue with the sides 8of each barb 6 facing in the direction of motion. Connector 2 willprevent movement of tissue in the direction in which it was inserted. Apair of connectors 2 inserted adjacent to each other and in oppositedirections will prevent movement of tissue in either direction across awound.

Connector 2 can be formed of a material sufficiently hard for point 9 topierce tissue and enable the connector to be inserted in tissue when asubstantially axial force is applied to body 4. Connector 2 ispreferably composed of a bioabsorbable compound, such as a polyglycolicacid or polylactic acid polymer or copolymer. The use of a bioabsorbablematerial eliminates the necessity of removing the connector from thepatient, which can be a painful and possibly dangerous process.Connector 2 can be formed, for example, by injection molding.

In one representative example of connector 2 for use in muscular tissue,the body 4 is formed from polyglycolic acid, has a length of 1 to 5 cm,and a diameter of about 1 mm. The diameter of a circle extending aroundpoints 7 of barbs 6 will be about 3 mm, and the barbs are spaced apartfrom each other on body 4 by a distance of 1 mm. Side 8 forms an angleof 135 degrees with the body 4 and side 10 forms an angle of 75 degreeswith the body 4.

In FIG. 3, there is shown a second embodiment of the present inventionin which barbs 16 are arranged in a uniform bidirectional configurationon a barbed tissue connector 12. Barbs 16 are constructed in the samemanner as barbs 6 on connector 2. A first set of barbs 15 on connector12 are arranged in a helical pattern and face a pointed end 20, and asecond set of barbs 16 on connector 12 are arranged in a helical patternand face a pointed end 21. Each of the pointed ends 20, 21 should besufficiently hard and sharp to easily penetrate tissue in which theconnector is to be used. Connector 12 is particularly suitable forapplications where the edges of a wound are prone to separate. Connector12 can be used by inserting one of the ends, for example end 20, into afirst side of a wound (not shown), spreading the wound slightly toexpose the second side of the wound, inserting the end 21 of theconnector 12 into the second side of the wound, and then pressing theedges of the wound together. The barbs 15 and 16 on the ends of theconnector 12 will grasp the tissue on each side of the wound and preventthe edges of the wound from spreading.

With reference to FIG. 4, there is shown another embodiment of thepresent invention in which a barbed tissue connector 22 has a nonuniformbidirectional configuration. Connector 22 comprises a pointed end 23 andone or more barbs 26 facing a first direction which alternate with oneor more barbs 27 facing a second direction. At each axial location,there can be a number, e.g. 4-9, of circumferentially-spaced barbs 26 or27. To insert connector 22 into tissue, the surgeon would use aninserting device 80 as described below. The arrangement of barbs 26, 27on connector 22 would prevent any localized movement of tissue relativeto the connector in an axial direction.

With reference to FIG. 5, there is shown another embodiment of thepresent invention in which a barbed tissue connector 32 has a uniformbidirectional configuration. Connector 32 comprises a body 34 havingpointed ends 33 and 35. A plurality of axially-spaced barbs 36 adjacentpointed end 33 face toward end 35, and a plurality of axially-spacedbarbs 37 adjacent pointed end 35 face toward end 33. Barbs 36 and 37 canbe circumferentially-spaced around body 34 at each axial location, orthe barbs 36 and 37 can be of the same construction and arranged in thesame pattern as barbs 6 on connector 2. To insert a connector 32, thesurgeon would use an inserting device 80 as described below. If the body34 of the connector 32 is sufficiently rigid, the connector 32 wouldprevent tissue retained by the barbs 36 from moving toward end 35 andtissue retained by barbs 37 from moving toward end 33. It will beapparent that only one end of connector 32 needs to be pointed; twopointed ends are preferable, however, so that the surgeon does not haveto take the time to insure that connector 32 is oriented in theinserting device 80 with a pointed end protruding from the insertingdevice.

With reference to FIGS. 6 and 7, there is shown another embodiment ofthe present invention in which a barbed tissue connector 42 comprises abody 44 having a pointed end 45 for penetration into tissue. A head 47is formed on an opposite end of body 44. A plurality ofcircumferentially-spaced barbs 46 are formed on body 44 at each of anumber of axial locations. As shown in FIG. 7, three barbs 46 are formedat each axial location; however, more or less than three barbs 46 couldbe used for certain applications. Barbs 46 include a first side 48formed at an obtuse angle to the body 44 and a second side 49 whichprojects from body 44 at an acute angle. The connector 42 can be forcedinto tissue by applying a force to the head 47. The connector 42 can beapplied by hand, or it can be inserted using an inserting device 80 asdescribed below.

The connector 42 can be formed entirely of a bioabsorbable material, orthe head 47 and the body 44 can be composed of different materials. Forexample, the body 44 can be composed of a bioabsorbable material, andthe head 47 can be composed of metal for superior strength and tofacilitate insertion of the connector 42. Head 47 can be made flat, asshown in FIG. 6, or the head can be formed by a single ring of barbs(not shown) facing in a direction opposite to that of the barbs 46.

In use, a series of connectors 42 can be inserted into tissue, such asalong the edges and in the field of a skin graft. After an adequateamount of time has passed for the wound to heal, the tissue beneath eachhead 47 could be depressed slightly to permit the head 47 to be cut fromthe body 44. The tissue would then rise up over the cut end of the body.Such a process would reduce scarring which could result from a long-termprojection of the body 44 through tissue and would eliminate thenecessity to remove connectors 42 from the patient.

With reference to FIGS. 8 and 9, there is shown another embodiment ofthe present invention in which a barbed tissue connector 52 has auniform unidirectional configuration. Connector 52 comprises a body 54having a non-circular cross-sectional shape. Body 54 includes aplurality of barbs 56 which are generally triangular in cross sectionand are equally spaced around the periphery of the body at a series ofaxial locations. Each of the barbs 56 includes a first side 58 disposedat an obtuse angle to body 54 and a second side 60 disposed at an acuteangle to the body. Body 54 includes a pointed end 53 to facilitate entryin tissue. Use of a non-circular cross-sectional shape increases thesurface area of the connector 52 and facilitates the formation of themultiple barbs on the connector. For example, barbs 56 can be formed ona piece of stock having a triangular cross section by removing materialat successive axial locations from the three edges of the stock. It willbe apparent that a similar process could be used to form barbs on stockof a different cross section (not shown), for example, a rectangular orhexagonal cross section.

In the use of the disclosed connectors, such as connectors 2 and 42, thesurgeon can grip the connector in one hand and push the connector intothe tissue. As an alternative to directly inserting the connectors intothe tissue, the surgeon can use an inserting device 80 as shown in FIGS.10 and 11. The inserting device 80 comprises a circular tubular body 82.The tubular body 82 can be generally arcuate in an axial direction, andthe body 82 is sufficiently long to contain at least a portion of abarbed tissue connector C. Device 80 has an inwardly tapered leading end84 and an outwardly tapered, or flared, trailing end 86. A handle 83 isprovided on body 82 adjacent trailing end 86 to enable the surgeon tomanipulate the inserting device 80.

In order to facilitate entry of the connector C and the device 80 intotissue, a connector C is positioned in tubular body 82 with a pointedend P of the connector C extending from leading end 84. In a preferredembodiment, the interior diameter of the body 82 is made slightlysmaller than the outside diameter of the connector C so that the barbs Bof a connector C in the body 82 will press against the body 82; as aresult, the connector C will be retained in the body 82 during insertionin tissue with the point P properly positioned outside of the body 82.The connector can also be positioned in body 82 with a barb B outside ofbody 82 to insure that the connector C will not be pushed back in thebody 82 during insertion. In one application of device 80, the surgeoninserts the body 82 having connector C therein into the patient's tissue87 until the connector C reaches a desired position, for example, theposition shown in FIG. 11. Device 80 is then withdrawn in the directionof arrow 90, and a barb, or barbs, B on the connector C penetrates andcatches the tissue 87 to hold the connector C in the inserted position.

Use of the inserting device 80 is particularly recommended when theconnector C includes multiple barbs facing more than one direction, suchas connectors 22 and 32, or when the connector is too flexible forinsertion without additional support.

While the present invention has been described with respect to certainpreferred embodiments thereof, it is to be understood that numerousvariations in the details of construction, the arrangement andcombination of parts, and the type of materials used may be made withoutdeparting from the spirit and scope of the invention.

1. A tissue connector comprising: an elongated body having a first end,a second end, a periphery, and a plurality of protrusions projectingfrom said periphery of the body, wherein a first portion of saidprotrusions extend along a portion of said body and are oriented in onedirection and a second portion of said protrusions extend along anotherportion of said body and are oriented in an opposite direction, theprotrusions being adapted to grasp tissue in one direction of movementof the connector through tissue and are not adapted to grasp tissue inan opposite direction of movement of the connector through tissue; andwherein at an axial location of said body, three of said protrusions areabout equally positioned about the periphery of the body.
 2. The tissueconnector of claim 1 wherein: said three protrusions are spaced atintervals of about 120 degrees about the periphery of the body at across-section.
 3. The tissue connector of claim 1 wherein: at each of aplurality of axial locations of said body, three said protrusions,oriented in one direction, are about equally and circumferentiallyspread about the circular periphery of the body.
 4. A tissue connectorcomprising: an elongated body having a first end, a second end, aperiphery, and a plurality of protrusions projecting from said peripheryof the body, wherein said protrusions extend along a portion of saidbody and are oriented in one direction, the protrusions are adapted tograsp tissue in one direction of movement of the connector throughtissue and are not adapted to grasp tissue in an opposite direction ofmovement of the connector through tissue; and wherein at an axiallocation of said body, three of said protrusions are about equallypositioned about the periphery of the body.
 5. The tissue connector ofclaim 4 wherein: said three protrusions are spaced at intervals of about120 degrees about the periphery of the body at a cross-section.
 6. Thetissue connector of claim 4 wherein: said body periphery is one oftriangular shaped and cylinder shaped.
 7. The tissue connector of claim4 wherein: said body periphery is non-circular cross-sectional shape. 8.The tissue connector of claim 4 wherein: said protrusions are triangularin cross-section.
 9. The tissue connector of claim 4 wherein: whereinsaid body is triangular shaped with three edges and said protrusions areformed into said edges.
 10. The tissue connector of claim 4 wherein:said body is one of rectangular shaped with edges and hexagonal shapedwith edges, and said protrusions are located respectively one the edgesof the rectangular shaped body and on the edges of the hexagonal shapedbody.
 11. The tissue connector of claim 4 wherein: at said axiallocation of said body one of less than three protrusions and more thanthree protrusions are formed.
 12. The tissue connector of claim 4wherein: connector is formed of one of a bioabsorbable material and anon-bioabsorbable material.
 13. The tissue connector of claim 4 wherein:said connector is formed of a first material and a second material withsuperior strength to said first material.
 14. The tissue connector ofclaim 4 wherein: said body is made of bioabsorbent material consistingof one of: polyglycolic acid polymer, polyglycolic acid copolymer,polylactic acid polymer and polylactic acid copolymer.
 15. The tissueconnector of claim 4 wherein: said protrusions are arranged in a helicalpattern on the body.
 16. The tissue connector of claim 4 wherein: saidconnector is configured to minimize at least one of scarring and tissuenecrosis.
 17. The tissue connector of claim 4 including: a needle at thefirst end of the body and an anchor at the second end of the body. 18.The tissue connector of claim 4 wherein said protrusions are barbs. 19.The tissue connector of claim 4 wherein said tissue connector is aone-way tissue connector.
 20. A tissue connector comprising: anelongated body with a circular cross-sectional shape having a first end,a second end, a circular periphery, and a plurality of protrusionsprojecting from said circular periphery of the body, wherein saidprotrusions extend along a portion of said body and are oriented in onedirection, the protrusions are adapted to grasp tissue in one directionof movement of the connection through tissue and are not adapted tograsp tissue in an opposite direction of movement of the connectionthrough tissue; and wherein at each of a plurality of axial locations ofsaid body, three said protrusions, oriented in one direction, are aboutequally and circumferentially spread about the circular periphery of thebody.